NewPipe

-Supply and scrubber pipes can be run in parallel without connecting to each other
-Supply pipes will only connect to supply pipes, vents and Universal Pipe Adapters(UPAs)
-Scrubber pipes will only connect to scrubber pipes, scrubbers and UPAs
-Supply and scrubber pipes are offset along the x and y axes to prevent sprite overlap
-UPAs will connect to regular, scrubber and supply pipes, as well as anything else that connects to a regular pipe. UPAs will be used to interface between the supply/scrubber loops and atmos

code/ATMOSPHERICS/components/unary/unary_base.dm

@@ -1,7 +1,7 @@
 /obj/machinery/atmospherics/unary
 	dir = SOUTH
 	initialize_directions = SOUTH
-	layer = TURF_LAYER+0.1
+	//layer = TURF_LAYER+0.1
 
 	var/datum/gas_mixture/air_contents
 
@@ -46,8 +46,12 @@
 
 		for(var/obj/machinery/atmospherics/target in get_step(src,node_connect))
 			if(target.initialize_directions & get_dir(target,src))
-				node = target
-				break
+				var/c = check_connect_types(target,src)
+				if (c)
+					target.connected_to = c
+					src.connected_to = c
+					node = target
+					break
 
 		update_icon()
 		update_underlays()

code/ATMOSPHERICS/components/unary/vent_pump.dm

@@ -18,7 +18,9 @@
 	use_power = 1
 	idle_power_usage = 150		//internal circuitry, friction losses and stuff
 	active_power_usage = 7500	//This also doubles as a measure of how powerful the pump is, in Watts. 7500 W ~ 10 HP
-	
+
+	connect_types = list(1,2) //connects to regular and supply pipes
+
 	var/area/initial_loc
 	level = 1
 	var/area_uid
@@ -64,7 +66,7 @@
 /obj/machinery/atmospherics/unary/vent_pump/New()
 	..()
 	air_contents.volume = ATMOS_DEFAULT_VOLUME_PUMP
-	
+
 	icon = null
 	initial_loc = get_area(loc)
 	if (initial_loc.master)
@@ -87,13 +89,13 @@
 	air_contents.volume = ATMOS_DEFAULT_VOLUME_PUMP + 800
 
 /obj/machinery/atmospherics/unary/vent_pump/update_icon(var/safety = 0)
-	if(!check_icon_cache())
+	if(!check_icon_cache())
 		return
 	if (!node)
 		on = 0
 
 	overlays.Cut()
-	
+
 	var/vent_icon = "vent"
 
 	var/turf/T = get_turf(src)
@@ -102,7 +104,7 @@
 
 	if(T.intact && node && node.level == 1 && istype(node, /obj/machinery/atmospherics/pipe))
 		vent_icon += "h"
-		
+
 	if(welded)
 		vent_icon += "weld"
 	else if(!powered())
@@ -121,7 +123,10 @@
 		if(T.intact && node && node.level == 1 && istype(node, /obj/machinery/atmospherics/pipe))
 			return
 		else
-			add_underlay(T, node, dir)
+			if(node)
+				add_underlay(T, node, dir, node.icon_connect_type)
+			else
+				add_underlay(T,, dir)
 
 /obj/machinery/atmospherics/unary/vent_pump/hide()
 	update_icon()
@@ -138,7 +143,7 @@
 
 /obj/machinery/atmospherics/unary/vent_pump/process()
 	..()
-	
+
 	if (!node)
 		on = 0
 	if(!can_pump())
@@ -150,27 +155,27 @@
 	var/datum/gas_mixture/environment = loc.return_air()
 
 	var/power_draw = -1
-	
+
 	//Figure out the target pressure difference
 	var/pressure_delta = get_pressure_delta(environment)
 	//src.visible_message("DEBUG >>> [src]: pressure_delta = [pressure_delta]")
 
 	if((environment.temperature || air_contents.temperature) && pressure_delta > 0.5)
-		if(pump_direction) //internal -> external	
+		if(pump_direction) //internal -> external
 			var/output_volume = environment.volume * environment.group_multiplier
 			var/air_temperature = environment.temperature? environment.temperature : air_contents.temperature
 			var/transfer_moles = pressure_delta*output_volume/(air_temperature * R_IDEAL_GAS_EQUATION)
 			//src.visible_message("DEBUG >>> [src]: output_volume = [output_volume]L; air_temperature = [air_temperature]K; transfer_moles = [transfer_moles] mol")
-			
+
 			power_draw = pump_gas(src, air_contents, environment, transfer_moles, active_power_usage)
 		else //external -> internal
 			var/output_volume = air_contents.volume + (network? network.volume : 0)
 			var/air_temperature = air_contents.temperature? air_contents.temperature : environment.temperature
 			var/transfer_moles = pressure_delta*output_volume/(air_temperature * R_IDEAL_GAS_EQUATION)
-			
+
 			//limit flow rate from turfs
 			transfer_moles = min(transfer_moles, environment.total_moles*MAX_SIPHON_FLOWRATE/environment.volume)	//group_multiplier gets divided out here
-			
+
 			power_draw = pump_gas(src, environment, air_contents, transfer_moles, active_power_usage)
 
 	if (power_draw < 0)
@@ -182,13 +187,13 @@
 		last_power_draw = handle_power_draw(power_draw)
 		if(network)
 			network.update = 1
-	
+
 	return 1
 
 /obj/machinery/atmospherics/unary/vent_pump/proc/get_pressure_delta(datum/gas_mixture/environment)
 	var/pressure_delta = DEFAULT_PRESSURE_DELTA
 	var/environment_pressure = environment.return_pressure()
-	
+
 	if(pump_direction) //internal -> external
 		if(pressure_checks & PRESSURE_CHECK_EXTERNAL)
 			pressure_delta = min(pressure_delta, external_pressure_bound - environment_pressure) //increasing the pressure here
@@ -199,7 +204,7 @@
 			pressure_delta = min(pressure_delta, environment_pressure - external_pressure_bound) //decreasing the pressure here
 		if(pressure_checks & PRESSURE_CHECK_INTERNAL)
 			pressure_delta = min(pressure_delta, internal_pressure_bound - air_contents.return_pressure()) //increasing the pressure here
-	
+
 	return pressure_delta
 
 //Radio remote control
@@ -282,7 +287,7 @@
 
 	if(signal.data["checks_toggle"] != null)
 		pressure_checks = (pressure_checks?0:3)
-
+
 	if(signal.data["direction"] != null)
 		pump_direction = text2num(signal.data["direction"])
 
@@ -325,7 +330,7 @@
 	if(signal.data["init"] != null)
 		name = signal.data["init"]
 		return
-
+
 	if(signal.data["status"] != null)
 		spawn(2)
 			broadcast_status()

code/ATMOSPHERICS/components/unary/vent_scrubber.dm

@@ -9,6 +9,8 @@
 	active_power_usage = 7500	//This also doubles as a measure of how powerful the pump is, in Watts. 7500 W ~ 10 HP
 	var/last_power_draw = 0
 
+	connect_types = list(1,3) //connects to regular and scrubber pipes
+
 	level = 1
 
 	var/area/initial_loc
@@ -29,7 +31,7 @@
 /obj/machinery/atmospherics/unary/vent_scrubber/New()
 	..()
 	air_contents.volume = ATMOS_DEFAULT_VOLUME_FILTER
-	
+
 	icon = null
 	initial_loc = get_area(loc)
 	if (initial_loc.master)
@@ -70,7 +72,10 @@
 		if(T.intact && node && node.level == 1 && istype(node, /obj/machinery/atmospherics/pipe))
 			return
 		else
-			add_underlay(T, node, dir)
+			if(node)
+				add_underlay(T, node, dir, node.icon_connect_type)
+			else
+				add_underlay(T,, dir)
 
 /obj/machinery/atmospherics/unary/vent_scrubber/proc/set_frequency(new_frequency)
 	radio_controller.remove_object(src, frequency)
@@ -130,7 +135,7 @@
 	if(scrubbing)
 		//limit flow rate from turfs
 		var/transfer_moles = min(environment.total_moles, environment.total_moles*MAX_SCRUBBER_FLOWRATE/environment.volume)	//group_multiplier gets divided out here
-		
+
 		power_draw = scrub_gas(src, scrubbing_gas, environment, air_contents, transfer_moles, active_power_usage)
 	else //Just siphon all air
 		//limit flow rate from turfs
@@ -145,14 +150,15 @@
 		last_flow_rate = 0
 	else
 		last_power_draw = handle_power_draw(power_draw)
-	
+
 	if(network)
 		network.update = 1
-	
+
 	return 1
 
 /obj/machinery/atmospherics/unary/vent_scrubber/hide(var/i) //to make the little pipe section invisible, the icon changes.
 	update_icon()
+	update_underlays()
 
 /obj/machinery/atmospherics/unary/vent_scrubber/receive_signal(datum/signal/signal)
 	if(stat & (NOPOWER|BROKEN))
@@ -186,7 +192,7 @@
 		scrubbing = !scrubbing
 
 	var/list/toggle = list()
-	
+
 	if(!isnull(signal.data["co2_scrub"]) && text2num(signal.data["co2_scrub"]) != ("carbon_dioxide" in scrubbing_gas))
 		toggle += "carbon_dioxide"
 	else if(signal.data["toggle_co2_scrub"])